Diurnal metabolic profiles after 14 d of an ad libitum high-starch, high-sucrose, or high-fat diet in normal-weight never-obese and postobese women

BACKGROUND: The influence of the amount and type of carbohydrates in the diet on risk factors for obesity, diabetes, and cardiovascular disease remains unclear. OBJECTIVE: We investigated the effects of 2 low-fat diets (high-sucrose and high-starch) and a high-fat diet on glycemia, lipidemia, and hormonal responses in never-obese and postobese women. DESIGN: Eighteen normal-weight women (8 postobese and 10 never-obese) consumed 3 ad libitum diets (high-fat, high-starch, and high-sucrose) for 14 d each. On day 15, we measured fasting and postprandial glucose, lactate, insulin, triacylglycerol, nonesterified fatty acids (NEFA), glycerol, glucagon, glucose-dependent insulinotropic polypeptide, and glucagon-like peptide 1. RESULTS: The high-sucrose diet induced significantly lower total areas under the curve (AUCs) for glucose and NEFA and a significantly higher lactate AUC than did the high-fat and high-starch diets; there were no significant differences in the insulin AUCs. The triacylglycerol AUC was greater with the high-fat and high-sucrose diets than with the high-starch diet. Gastrointestinal hormone concentrations differed between diets, but not between the 2 subject groups. Comparisons between subject groups for all diets combined showed lower relative insulin resistance and lower AUCs for glucose, insulin, and triacylglycerol in the postobese group. CONCLUSIONS: High-starch and high-sucrose diets had no adverse effects on postprandial glycemia, insulinemia, or lipidemia compared with a high-fat diet. A sucrose-rich diet may improve glucose metabolism, but may have an adverse effect on lipidemia, compared with a starch-rich diet. Postobese women seemed to be more insulin-sensitive and more efficient at storing triacylglycerol than were never-obese women, regardless of dietary composition.